Major League Baseball's investigation into the link between the now-shuttered Biogenesis anti-aging clinic and performance-enhancing substances provided to more than a dozen players culminated in Monday's announcement that 13 players have been suspended.

Yankees third baseman Alex Rodriguez topped the list on one of the most significant disciplinary days in baseball history. MLB handed down a suspension that would sideline the 38-year-old Rodriguez without pay through the end of the 2014 regular season.

Rodriguez will appeal, and in his first game back on Monday, he went 1-for-4, singling in his first at-bat, in the Yankees' 8-1 loss to the White Sox. The game was his season debut following offseason hip surgery. He will be eligible to play until his case is heard by arbitrator Fredric Horowitz. There was speculation that might not happen until November or December, according to Major League Baseball Players Association executive vice president Michael Weiner.

As opposed to salary-arbitration cases, an arbitrator making a ruling on a suspension has the power to adjust a player's suspension to whatever length he considers most appropriate.

Rodriguez's discipline, MLB said in its written announcement, is based on his use and possession of numerous forms of prohibited performance-enhancing substances, including testosterone and human growth hormone, over the course of multiple years. Rodriguez's discipline under the basic agreement is for attempting to cover up his violations of the program by engaging in a course of conduct intended to "obstruct and frustrate" the investigation.

His suspension, effective on Thursday, encompasses 211 regular-season games and any 2013 postseason games in which Rodriguez otherwise would have been eligible to play. His suspension was stayed under the terms of the Joint Drug Prevention and Treatment Program.

A free agent, Norberto's suspension would be effective immediately once he signs with another Major League organization. All other suspensions are effective immediately.

RULES FOR SUSPENDED PLAYERS

What they can't do:

Cannot receive pay

Cannot participate in Arizona Fall League

Cannot participate in Postseason games

Cannot be elected or selected to the All-Star Game (if player is suspended during the offseason, Spring Training, or championship season prior to the All-Star Game)

What they can do:

Can participate in Spring Training and extended spring training

Can participate in affiliated Winter League games

Can work out with the club

Can participate in batting practice before the gates open before a game

Can consent to an assignment to a Minor League affiliate for a period of time prescribed under Section 7.H.2 of the Joint Drug Program

Blue Jays outfielder Melky Cabrera, Athletics pitcher Bartolo Colon and Padres catcher Yasmani Grandal, all of whom already have served 50-game suspensions as a result of their violations of the drug program stemming from their connections to Biogenesis, will not receive additional discipline.

While early reports on Biogenesis included the names of Nationals left-hander Gio Gonzalez and Orioles infielder Danny Valencia, the investigation found no violations by either player.

All the suspended players except Rodriguez accepted MLB's punishment and will be able to return in the postseason or start fresh next season. Brewers All-Star left fielder Ryan Braun agreed to a season-ending 65-game punishment last month.

"Despite the challenges this situation has created during a great season on the field, we pursued this matter because it was not only the right thing to do, but the only thing to do," Commissioner Bud Selig said. "For weeks, I have noted the many players throughout the game who have strongly voiced their support on this issue, and I thank them for it."

Players across baseball applauded Selig's actions.

"Ultimately, although today will be a day of infamy for MLB, it is a tremendous step in the right direction for the game we love," tweeted Rays star Evan Longoria.

Said Nationals All-Star third baseman Ryan Zimmerman: "It's good for the sport. ... We still need to continue to make the test tougher so it's harder to cheat."

Added Padres catcher Nick Hundley, who saw his teammate, Everth Cabrera, suspended: "While this is disappointing for the organization, it's an exciting time for the game to be cleaned up."

"I made a mistake," said Cabrera, who didn't take questions but spoke in detail of the events that led to him taking a banned substance in 2012.

Cruz and Peralta are playing for teams well-positioned to make the postseason; Cruz decided only at the last moment not to file a grievance and the Tigers acquired Jose Iglesias from the Red Sox at last week's non-waiver Trade Deadline in order to have a shortstop to play in Peralta's absence. Any player who accepted penalties through the end of the regular season would be eligible for the playoffs.

"In spring of 2012, I made a terrible mistake that I deeply regret," Peralta said. "I apologize to everyone that I have hurt as a result of my mistake, including my teammates, the Tigers organization, the great fans in Detroit, Major League Baseball and my family. I take full responsibility for my actions, have no excuses for my lapse in judgment and I accept my suspension."

Cruz said he used PEDs to recover after losing 40 pounds due to a gastrointestinal infection that affected him during the 2011-12 offseason.

"By the time I was properly diagnosed and treated, I had lost 40 pounds," Cruz said. "Just weeks before I was to report to Spring Training in 2012, I was unsure whether I would be physically able to play. Faced with this situation, I made an error in judgment that I deeply regret, and I accept full responsibility for that error. I should have handled the situation differently, and my illness was no excuse.

"I look forward to regaining the trust and respect of the Rangers organization, my teammates and the great Rangers fans, and I am grateful for the opportunity to rejoin the team for the playoffs."

It remains to be seen if players whose teams make the postseason can remain sharp enough to contribute after a two-month layoff. When Melky Cabrera was suspended in the second half of last season, the Giants chose not to bring him back for the playoffs.

Monday's developments are the latest signals that both MLB and the Major League Baseball Players Association are serious about ridding the game of steroids, human growth hormone and other substances. In January, random unannounced blood tests for HGH and offseason testing for synthetic testosterone were added to the league's drug program.

"This case resoundingly illustrates that the strength of our program is not limited only to testing," Selig said. "We continue to attack this issue on every front -- from science and research, to education and awareness, to fact-finding and investigative skills. Major League Baseball is proud of the enormous progress we have made, and we look forward to working with the players to make the penalties for violations of the drug program even more stringent and a stronger deterrent.

"As a social institution with enormous social responsibilities, baseball must do everything it can to maintain integrity, fairness and a level playing field. We are committed to working together with players to reiterate that performance-enhancing drugs will not be tolerated in our game."

There had been reports that MLB was threatening Rodriguez with a lifetime ban or that Selig would seek to suspend him under the Basic Agreement's "best interests of baseball" clause that would have precluded him from playing while his appeal was heard.

"The accepted suspensions announced today are consistent with the punishments set forth in the Joint Drug Agreement, and were arrived at only after hours of intense negotiations between the bargaining parties, the players and their representatives," MLBPA executive director Michael Weiner said. "For the player appealing, Alex Rodriguez, we agree with his decision to fight his suspension. We believe that the Commissioner has not acted appropriately under the Basic Agreement. Mr. Rodriguez knows that the union, consistent with its history, will defend his rights vigorously."

There also have been reports that Rodriguez, the highest-paid player in baseball, is intent on preserving as much of his money as possible. Next season alone he is scheduled to make $25 million. If his appeal is denied and he serves out his suspension, there will still be $61 million left on the final three years of his contract, 2015-17.

The Yankees issued a statement in which they expressed "full support" of MLB's drug program while also addressing remarks made last week by Rodriguez, who accused the team of being mostly interested in getting out from under Rodriguez's contract.

"We are in full support of Major League Baseball's Joint Drug Prevention and Treatment Program," the Yankees said. "We also recognize and respect the appeals process. Until the process under the drug program is complete, we will have no comment. We are confident that the process outlined in the drug program will result in the appropriate resolution of this matter. In the meantime, the Yankees remain focused on playing baseball.

"However, we are compelled to address certain reckless and false allegations concerning the Yankees' role in this matter. The New York Yankees in no way instituted and/or assisted MLB in the direction of this investigation; or used the investigation as an attempt to avoid its responsibilities under a player contract; or did its medical staff fail to provide the appropriate standard of care to Alex Rodriguez.

"Separately, we are disappointed with the news today of the suspension of Francisco Cervelli. It's clear that he used bad judgment."

The World Anti-Doping Agency commended the suspensions.

"As we have said previously, non-analytical methods are proving to be an increasingly effective means of helping uncover those athletes who have committed foul play and breached anti-doping rules," WADA said in a statement. "MLB has approached the matter in a professional manner throughout, and we look forward to maintaining our close relationship as we move forward in our efforts to protect clean athletes and advocate doping-free sport."

Paul Hagen is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.